Digital signatures and signcryption schemes on embedded devices: a trade-off between computation and storage

This paper targets the efficient implementation of digital signatures and signcryption schemes on typical internet-of-things (IoT) devices, i.e. embedded processors with constrained computation power and storage. Both signcryption schemes (providing digital signatures and encryption simultaneously) and digital signatures rely on computation-intensive public-key cryptography. When the number of signatures or encrypted messages the device needs to generate after deployment is limited, a trade-off can be made between performing the entire computation on the embedded device or moving part of the computation to a precomputation phase. The latter results in the storage of the precomputed values in the memory of the processor. We examine this trade-off on a health sensor platform and we additionally apply storage encryption, resulting in five implementation variants of the considered schemes.